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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Obstetric and perinatal outcome in human immunodeficiency virus-infected pregnant women with and without opiate addiction.
No full textThis study was undertaken to assess the impact on gestation played by the simple human immunodeficiency virus (HIV)-seropositive status either alone or complicated by opiate abuse in the absence of other confounding variables. To this purpose the main obstetric complications and the perinatal outcome were prospectively evaluated in 38 simple HIV-infected women, 14 of whom were simple carriers and 24 under methadone treatment, and in 76 uninfected women, 16 of whom were methadone users and 60 controls. In simple HIV-carriers maternal weight gain (P < 0.001) and both 1- and 5-min Apgar scores (P < 0.005) were reduced whereas the incidence of miscarriage was increased (P < 0.05). Worse obstetric and perinatal outcomes were found in HIV-seropositive drug addicts, in which gestational length (P < 0.001), maternal weight gain (P < 0.001) and Apgar scores were lower (P < 0.005 and P < 0.001, respectively) and the rate of preterm labour, small for gestational age newborns, vaginal and urinary infections as well as of unexplained fever (P < 0.05) was higher. Outcomes were similar in HIV-seropositive and seronegative drug addicts and in both groups a positive correlation (r = 0.62 P < 0.001, and r = 0.44, respectively) was found between the number of infectious episodes throughout pregnancy and the mean dose of opiate consumed daily. Our results suggest that HIV-seropositive condition might exert slight direct and indirect detrimental effects on pregnancy. Whatever the maternal serologic status, opiate intake not only causes a further worsening of gestational and perinatal outcomes, but also increases the susceptibility towards pathogens
Visualization of aggregation and internalization of the epidermal growth factor-receptor complex in the human chorion laeve at term gestation
No full textObjective: The present study was conducted to evaluate whether receptor-mediated endocytosis of epidermal growth factor occurs in human chorion laeve at term gestation. Methods: Electron microscopy examination of labeled epidermal growth factor-receptor complexes. Results: Epidermal growth factor-receptor complexes were found to aggregate on cell surface and subsequently become internalized into endocytic vescicles just beneath the cell surface. Conclusion: Receptor-mediated endocytosis of epidermal growth factor is operative in the human chorion at term and, consistent with the hypotesis that epidermal growth factor-receptor in the above tissues are functionally active
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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